I must be a lucky guy. I have about three bad eggs on my Diamond that have not done a thing to my game. Although, the game has been through a lot. First off, it's been threw a washer and drier about five times. Second, it was dropped in ranch. Third, I forgot to disable the run through walls cheat and ran through the wall in the Union Room (NEVER DO THAT) and turned into a ghost of sorts. I could see a shadow and couldn't go any where or talk to anything. I restarted and have hacked pokemon (use it to get fun teams and see shiny pokemon, I'm no dirtbag that puts 'em online) sometimes they turn into bad eggs at random. I move the eggs and haven't bothered them since and nothing else has happened.

Oh, and use a insta-box pokemon code to get rid of them. My game hasn't had any issues since.